Process of obtaining water-soluble potassium compounds



' Patented Aug. 21, 1923.

hair ,-.srrrss t [t etse Brennan 1). cnn'nsrian, vor onnnsnn, MICHIGAN, Ann ROBERT cfn'arr, tam.

.ennsrown, MARYLAND, essrenons', frnnoi'rirnrron cot'irAnY, on LOS ceLIron IA.

a raoonss or No Drawing;

To all whom it may concern:

Be it known that we, RICHARD D. CHEF-S- MAN and Bonner (1- Hnrnciti'zens of the United States,and residents of Chelsea,-in the county of Washtenaw and State 0' Michigan, and rl'agerstown, in the. county of Washington and State of Maryland, respectlvely, have invented new and useful improvements in Processes of Obtaining ater-Soluble Potassium Compounds, of

which the t llowing isa specification.

The present invention relates to a process of obtaining water soluble,' or readily water soluble, potassium compounds, and has particular reference tofsuch a process for increasing the yield of 'the water soluble, or readily water soluble, 00111 pounds, obtainable from dust, gases, or a mixture thereof, occurring during the production of Portland cement.

The invention is founded upon the dis cor'ery that the insolubility, or imperfect solubility of potassium compounds, which are present inthe dust, gases, or mixture thereof, as above indicated, is caused by'the combination of the'volatile potassium compounds with the ash constituents of the.

coal. These ash constituents result from the combustion of the powdered coal, em ployed in the process of producing Portland cement, as is 'well known. The soluble potassium compounds are measurably prevented from combining with the ash constituents and the proportion of the potassium compounds which is retained in a soluble form is increased. For accomplishing this result, the alkali metal compound, such as sodium chloride, may be mixed with the powdered coal, or it may be introduced into the raw mix.

In the practice oi our process in its preferred form, a suitable amount of an alkali metal compound such as sodium chloride or salt, is intimately mixed with the powdered coal, in suitable proportions Application filed as 24,

BY ivrnsnn assrernianrrrs, To wnsrnnn enemas, oALIsoait1a,'n coaronja'rron or onrarn 'ne WATER-sonnets rorassiuar ooMroUnnsQ i917. serau no; 170,740.

percent by weight of the sodium chloride'or salt. We'preter to addthesodium chloride or salt to the powdered coal and intimately mix the same therewith, as this brings the sodium chloride in close contact with the ashcontents, but the invention is not neces-. sarily restricted to this specific manneroi introducing sodium chloride, as satisfactory results are-obtainable by adding the same i to the raw mix, or otherwise introducing the same into the kiln because at the. temperature of the kiln the salt is largely volatilized and thus has an opportunity to mix with and act'on the fine particles of ash floating in the gases of the kilns. j

The constituents of Portland cement, such as clay. and lime stone, are finely divided or ground and introduced into a r0- tary kiln. This mixture is then subjected to the action of heat and products of com bustionwhich enter the kiln, .rromsuit: able burners employing the mixture, of

powdered coal and sodium chloride or salt, as fuel.

The additionof sodium chloride, to the powdered coal used in burning to the extent proposed, amounting as it does to 6% of the weight of the coal, might be expecte'd'to seriously interferewiththe in tensity and efficiency of suchcombustionf but our experience in actual practice has water soluble potassium compounds, are

suitably treated to recover such compounds.

In the practice of this process, we have also discovered that the additlon of the sodium chloride or salt to the cement kilns, the same being added to the coal dust or the raw mix, has the effect of increasing the ease with which the alkahes are dr1ven oflf irom the clinker. By the introduction into the kiln oi the sodium chloride, in the proportions stated, which is a relativelylarge amount of alkali, the conditions of operation within the furnace are so changed or modified, that when burned at any particular temperature, and contrary to what might be expected, the total amount of time believed to be thebest embodimentof our invention, but we do not wishto be' limited to the precise steps as set forth, nor

limit ourselves to the chemicals outlined above, and it is to be understood that the steps of the, processfmay'be modified in many different 'ways that may" fairly fall within the scope of the appended claims.

Having thus described our invention, what we claim 1s:

ing water soluble potassium compounds and Portland cement, which consists in mixing-v an alkali metal compound with coal, burning such mixture subjecting the constituents of a Portland cement mix to the direct action of the products of combustion from the mix ture whereby the cement, is formed and the water soluble potassium compounds are obtained'in thedust and gases which are given off by said'constituents, and treating the dust and gases to recover the water soluble potassium compounds contained therein.

2. The herein described process of obtain ing water soluble potassium compounds and Portland'cement, which consists in mixing a sodium compound with powdered 'coal,

' burning such mixture, subjecting the constituents of a Portland cement miX to the direct action of theproducts of combustion from the mixture whereby the cement is formed and the water soluble potassium compounds are obtained in the dust and gases which are given ofi by said constituents, and'collecting and treating the dust and gases to recover the water soluble potassium compounds.

3. The herein described process of obtaining water soluble potassium compounds and Portland cement, which consists-in introducing a containing the constituents ing oil the watersoluble pot'assiumfcom-' pounds and collecting and'jseparating out the water soluble potassium compounds.

A. In the manufacture of Portland cement with recovery of combined potassium by clinkering a potassiferousraw mix d1- rect firing with coal in a cement kiln' and collecting fumedeff potassium compounds;

, thenethod of increasing the proportion of V 1; The herein described process of Obi/3,111?

readily soluble combined potassium in the V dust and gases discharged from the rkiln,

which comprises additionally introducing into the kiln and into reacting proximity with the coal ash particles suspended-in the hot kiln atmosphere, a compound ot an allmlineoxid-torming metal capable of :reacting with said ash particles to oppose formation of diflicultly soluble combinations of the ash with combined potassium also pres ent in the kiln atmosphere. 7

5. In the manufacture of Portland cement with recovery of combined potassiunr by -method of increasing the proportion of readily soluble combined potassium in the dust and gasesdischarged from the kiln which comprises additionally introducing" into the kiln; and into reactingproximity with the coal ash part cles suspended-in the hot kiln atmosphere, an alkali'inetal com- 'poundcapable of reacting with said ash particles to oppose formation of diflicnltly soluble combinations of the ash with combined potassium also present in the kiln atmos' RICHARD n. cHE s Au' nonnnr o. HAFFV phere, 

